Crankcase Depression Regulator (CDR)

To test CDR valve, connect one hose of a water manometer to engine oil dipstick tube. See Fig 2. Leave other hose of manometer open to atmosphere. Install air cleaner and run engine. CDR valve specification is one inch of water pressure at idle to 3-4 inches at full load. Add amount of distance water travels down one side of gauge to distance water travels up other side of gauge to obtain reading.

Fig 1: Crankcase Depression Regulator Valve

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Fig 2: Crankcase Depression Regulator Valve Test (Typical)

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Fig 3: Crankcase Depression Regulator Valve & Hoses (Non-Turbo)

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Fig 4: Crankcase Depression Regulator Valve & Hoses (Turbo)

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